Our immediate aim is to expand the capability of the Biochemical Research Service Laboratory (BRSL) through the acquisition of an Applied Biosystems pulsed liquid protein/peptide sequencer. Addition of this instrument to the BRSL will enable that facility to greatly expand its protein/peptide sequence service which currently consists only of the Tarr manual procedure and amino acid analysis service. The six projects included in this proposal, plus an additional two to three projects not included, will benefit greatly from this expanded capability. The proteins being studied include protease nexin I, a "trypsin complexing" protein, adenosylhomocysteine hydrolase, monoclonal cryoglobulins, phenylethanolamine N-methyl-transferase, tubulin, formyltetrahydrofolate synthetase, a glutamate binding protein, and a (Ca2+ + Mg2+)-ATPase. The projects range from isolation and sequencing of affinity-labelled active site peptides, to partial sequencing for the purpose of synthesizing DNA probes, to complete sequence determination of a large protein. In addition to enhancing our productivity on currently funded projects this added capability will significantly alter the scope of studies we would consider doing in the future.